The impact of near-infrared photobiomodulation therapy on human oocyte rescue in vitro maturation

This prospective study investigated the effects of photobiomodulation therapy (PBMT) at 810 nm on rescue in vitro maturation (rescue-IVM) of human immature oocytes following controlled ovarian stimulation (COS). A total of 260 immature oocytes (germinal vesicles (GV): 143; metaphase I (MI): 117) were collected from 114 women undergoing COS between December 2023 and July 2025, denuded, and randomized into control or PBMT groups; ten in vivo -matured MII oocytes served as references. PBMT was applied at 810 nm, 1.0 W, 60 J/cm 2 for 1 min, and nuclear maturation and morphology were assessed up to 6 h of IVM. ATP content, mitochondrial oxidative phosphorylation (OxPhos) activity, and lipid peroxidation (MDA) were measured using luminometric, oximetric, and spectrophotometric assays. PBMT accelerated maturation, with GV and MI oocytes progressed to the next maturation stage 112.5% and 92.3% faster, respectively, within 1 h. ATP content increased markedly in PBMT-treated oocytes ( P < 0.0001), with early-resuming MI oocytes exceeding levels of in vivo MII oocytes. OxPhos activity increased by 240% (GV) and 194% (MI) immediately after irradiation without mitochondrial uncoupling, while MDA levels remained stable. Collectively, these results demonstrated that PBMT accelerated cell cycle progression to GV and MI oocytes by enhancing mitochondrial OxPhos and ATP production without inducing oxidative stress. Limitations include the need for larger cohorts, evaluation of safety through assessment of potential DNA damage, and validation in poor-prognosis or advanced maternal age patients. This pioneering proof-of-concept study highlights the potential of PBMT to temporally accelerate rescue-IVM of immature oocytes - and possibly cumulus-oocyte complexes - in poor-responder patients undergoing IVF or fertility preservation.